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    <script>
      //  实现一个计数器函数，每次调用该函数返回一个递增的数字

      //实现以下效果
      // const counter = createCounter();
      // console.log(counter()); // 1
      // console.log(counter()); // 2
      // console.log(counter()); // 3

      // let count = 0
      // function createCounter() {
      //   count++
      //   return count
      // }

      const createCounter = () => {
        let count = 0
        const fn = () => {
          count++
          return count
        }
        return fn
      }
      const counter = createCounter()
      console.log(counter())
      console.log(counter())
      console.log(counter())
    </script>
  </body>
</html>
